Otters (subfamily Lutrinae) are the aquatic branch of the splendid Mustelidae family which includes all sorts of highly successful predators like weasels, ferrets, polecats, otters, fishers, and wolverines. We have already described the giant river otter of the Amazon, a magnificent apex predator which lives on anacondas and piranhas but there are also 12 other species of otters living throughout the Americas, Eurasia, and North Africa (and in the ocean).
All of the otters partake of the tremendous strength (and weakness) of the Mustelidae family. They are ridiculously fast, powerful, and agile, but in order to keep up their swift lifestyles they have huge metabolic intake. This means they must eat all of the time, and as predators their life is one endless hectic hunt. Northern otters are at a particular disadvantage since they live in freezing rivers, lakes, and oceans. In cold weather, European river otters have to eat 15% of their weight every day, while Sea otters must daily down an incredible 25% of their mass. Fortunately a fast metabolism brings its own incredible reward: otters (like weasels and ferrets) seem to be effortlessly moving while everything else is standing still.
Otters eat a startling variety of prey. Although fish is the staple of their diet they also opportunistically eat snakes, frogs, lizards, birds, eggs, small mammals, mollusks, crustaceans, and sundry other invertebrates. Their need for calories keeps them from being too picky. Despite their speedy metabolisms, otters live as long as dogs (and can survive even longer in captivity). Different otters have different levels of sociability—the Oriental small clawed otters and the river otters are quite clannish and live in big playful groups.
In addition to being great hunters (and eaters) otters are famous for playing. Their frolicksome antics are a joy to behold, so I found some video on Youtube, but be warned: the sound on my computer is broken so I have no idea what the narrator/soundtrack/music is like. It might be slidewhistles or it might be 2 minutes and 56 second of the foulest curse words. Maybe you should watch it on mute.
Perhaps because otters seem to appreciate life, people have a reverence for them (not that reverence stopped furriers from nearly driving several species extinct during the course of the past three centuries). In the the shapeshifting dwarf Otr prefers to spend his time as an otter until he is killed by the malicious trickster god Loki. Loki is forced to cover the otter skin with treasure, but one whisker remains uncovered and so Loki was forced to part with his magic ring of power (which went on to wreak havoc, as magic ring inevitably do). To Zoroastrians, the otter was reckoned to be truly pure–and thus sacred to Ahura Mazda, the uncreated god who represents the apogee of wisdom, light, and goodness in their pantheon. So if, by bad luck, the evil dragon Ahriman happens to burn his way into this world and begins to destroy existence you might want to go be near some otters. You know, even without the evil dragon, you should go spend time watching otters. They’re just great animals.